Share your experience!
I am facing big problems in mobile data connection in my XPERIA Z. I can't access facebook, Goolge map, massenger, internet browser ,gmail.... though the signal is showing LTE . but when I make hot spot then other can use internet without any problem & also I connect laptop to hotspot I enjoy good internet speed.
If I can't use these apps then my XPERIA Z is useless .Please do something fast.
try doing a repair through Sony PC Companion or so to see if that fixes your problem if it does not then disable mobile data for a few seconds then enable it again and try apps again if it still fails then it sems to be a problem with your mobile unless it's something todo with your SIM card from phone company so ask them about problem
if they also claim that this is a known phone problem then you can let them repair it 
I've occasionally had problems like this with my XZ, my LTE XZ tablet, and my previous Motorola Xoom (with 4G). The answer is either turning on flight mode, wait 30 seconds, then turn off flight mode. OR reboot the device. I'd only repair it if these don't work, but I'd be very surprised if trying my and then Jake's suggestions did not fix it.
It's working fine before updating to os 4.2.2...
Have you tried doing a software repair on the handset since you started experiencing this issue?
I would also recommend speaking with your service provider as it sounds like you have a basic Internet access APN set up on the handset. You would need to obtain their settings for a full access Internet account and update these in Settings > More > APN.
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